diff --git a/esphome/core_config.py b/esphome/core_config.py
index 28f2254c65..840191d39d 100644
--- a/esphome/core_config.py
+++ b/esphome/core_config.py
@@ -38,7 +38,7 @@ def validate_board(value):
 
     if value not in board_pins:
         raise cv.Invalid(u"Could not find board '{}'. Valid boards are {}".format(
-            value, u', '.join(pins.ESP8266_BOARD_PINS.keys())))
+            value, u', '.join(sorted(board_pins.keys()))))
     return value